For those who think that you can simply build something “fluid” or “flexible,” it’s a lot harder than it seems. A lot of the industry jargon comes from print and the printing process; margins, padding, kerning, spacing, etc. There is no such thing as a fluid layout on a printing press (as far as I know :-). So we are stuck with a language to describe design based on a different era. Additionally, in the design phase…
Client education is a challenge and all, they often have ideas in mind that are very specific (For some reason clients invariably like the simplest thing that's the least general and most direct of a translation from a basic analog system...). But on the technical side... once you stop making designs that rely on being able to control exactly where everything goes it gets a lot easier.